1.The roles of acidity, peroxide and non-peroxide compounds in antibacterial properties of Malaysian Kelulut, Tualang and Acacia honey
Mohd Amir Shahlan Mohd-Aspar ; Raihana Edros ; Siti Umairah Mokhtar ; Norhidayah Kamarudin
Malaysian Journal of Microbiology 2023;19(no.3):291-300
Aims:
In this study, three putative factors that commonly contribute to antibacterial properties in honey were determined, namely acidity (pH level), peroxide compounds and non-peroxide compounds.
Methodology and results:
Honey samples were prepared based on the known factors of acidity, peroxide compounds,and non-peroxide compounds to identify factors that contribute to the antibacterial properties of the honey based on agar diffusion assay. Liquid chromatography quadropole time-of-flight mass spectrometry was employed to detect and quantify the presence of acidic, peroxide, and non-peroxide compounds in the honey samples. Acidity and non-peroxide compounds were identified as the significant factors contributing to the antibacterial properties of Kelulut, Tualang and Acacia honey. No peroxide compound was detected in this study across all honey samples. In Kelulut, the presence of the additional compounds (reptoside, platycogenic acid and kauranoic acid) may explain its higher antibacterial properties against Escherichia coli and Staphylococcus aureus as compared to Tualang and Acacia honey based on the inhibition zones on the agar plates.
Conclusion, significance and impact of study
The presence of multiple antibacterial factors in honey is notably important as it gives an advantage of using honey compared to antibiotics in preventing the growth of a wide range of bacterial species with multiple modes of action.
2.Preliminary studies on extraction of propolis using vitamin E d-ɑ-Tocopheryl polyethylene glycol succinate (vitamin E TPGS) and compare their antimicrobial activities
Yee Tong Kong ; Viviana Abdullah ; Siti Umairah Mokhtar ; Rajaletchumy Veloo Kutty
Malaysian Journal of Microbiology 2020;16(5):346-352
Aims:
Phenolic compounds with various biological activities such as antimicrobial, anti-inflammatory and antioxidative
activity are considered as key compounds in propolis. In this study, propolis was obtained in Kuantan, Pahang and is
known to be collected from stingless honey bee Trigona thoracica. The objective of this study is to extract propolis using
surfactant vitamin E d-α-Tocopheryl polyethylene glycol 1000 succinate (Vitamin E TPGS) and evaluate its antimicrobial
activity compared to water and ethanolic propolis extracts.
Methodology and results:
Quantitative determinations of phenolic acid and flavonoid such as caffeic acid and
quercetin, respectively in propolis extracts were conducted by using High Performance Liquid Chromatography (HPLC).
As a result, 70% ethanol extracted propolis (EEP), water extracted propolis (WEP) and 0.02% vitamin E TPGS extracted
propolis successfully demonstrate the presence of hydrophilic caffeic acid, while only 70% EEP and 0.02% vitamin E
TPGS extracted propolis show the presence of hydrophobic quercetin. Lastly, antimicrobial testing was conducted
towards Staphylococcus aureus by using all three different propolis extracts.
Conclusion, significance and impact of study
The results showed EEP and vitamin E TPGS propolis extracts exhibit
higher antimicrobial activity compared to the WEP.
Propolis
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Anti-Infective Agents